306 DIETETIC DEFICIENCY. 



are already in course of publication,* but a brief outline of the 

 work may be of interest here. 



The main scheme of experiment in so far as it bears on the 

 avitaminosis aspect of lainziekte may be indicated : — 



(a) An attempt was made to produce an avitaminosis in 

 cattle by feeding on a known deficient diet. For this purpose 

 polished rice was used, along with an extremely small ration of 

 veld hay or autoclaved straw, so as to minimise digestive disturb- 

 ance. If a recognisable disease had been ]>roduced, it could have 

 been compared symptomatically with lamziekte. No specific 

 disease was manifested, however, even after a full year of rice 

 feeding, and from this it was concluded that if an avitaminosis 

 exists in cattle at all, it must be a matter of very slow develop- 

 ment. This was also acce])ted as evidence against the probability 

 of lamziekte being an avitaminosis, since fresh cattle from a 

 non-laniziekte area may, \vhen brought on to an afifected area, 

 develop the disease in nmcli less than a year. 



(b) Feeding experiments with pigeons were carried out to 

 determine the antiberiberi value, or vitamine content, of a num- 

 ber of feeding stuffs which were fed as supplementary rations to 

 cattle on lamziekte veld. 



(c) Cattle grazing naturally over lamziekte veld were su])- 

 plied with rations containing vitamines in large excess of their 

 probable metabolic requirements, calculated on the basis of the 

 pigeon tests. The beriberi vitanu'ne was sttpplied in the form of 

 beans, bran, maize, and yeast. The scurvy vitamine was given 

 in the form of raw potatoes. The rate of mortality was then 

 compared amongst cattle which had received su])plementary feed- 

 ing and cattle which merely grazed on the lamziekte veld. No 

 difiference was apparent, and it was therefore concluded that lack 

 of vitamine Avas not the cause of lamziekte. 



(d) \'itamine extracts which were found highly curative for 

 pigeons suifering from " experimental beriberi " w^ere adminis- 

 tered to cattle sulTering from lamziekte. Tn no case could a cure 

 be efifected. This was regarded as evidence confirming the 

 results of the feeding experiments. 



{c) The rainfall and state of the herbage on the veld was 

 noted during the experimental period. Lamziekte occurred even 

 after heavy rains, wdien the veld vegetation was green and com- 

 paratively luxuriant. This was regarded as disposing of the view 

 that lowering of the vitamine content in the grass, through 

 drought, was causally related to the prevalence of the disease. 



From this rough summary of our experimental results, it 

 will be generally agreed that we are justified in concluding that 

 lamziekte is not an avitaminous of any recogn.ised type. 



Deficiency Disease in Cattle in General. — Resides our own 

 lamziekte. various other diseases in other parts of the world have 



* '' Contributions to the Study of Deficiency Disease,'' Theiler, Green, 

 and Viljoen, 1"hird Report of the Director of Veterinary Research. 



